Defects of articular joints are significant sources of pain, discomfort and disability. These defects, such as full-thickness chondral defects, may be associated with osteoarthritis or other disease, traumatic injury and/or age or use-related degeneration of articular cartilage. Morbidity associated with defects of hyaline cartilage comprised by articular joints is responsible for significant economic, health and social costs.
Current treatments for repair or amelioration of joint problems include microfracture, abrasion and drilling. These interventions involve exposing a joint containing a defect to mesenchymal stem cells. As a result of such interventions, the mesenchymal stem cells may infiltrate the defect, and differentiate into fibrocartilage over time. However, fibrocartilage has a structure and molecular composition distinct from that of the hyaline cartilage found in joints. Fibrocartilage generally provides only short-term improvement, typically lasting less than two years. Alternative treatments are, therefore, needed.